Tool retainer



C. R. ALDEN TOOL RETAINER May 23, 1933.

Filed July 12, 1929 Patented May 23, 1.933

UNITED STATES PA'raNr: essieu CARROLL La. ALBEN, or nnrnorr, MICHIGAN, nssreNoR, iaYMnsNn nssIGNMEN'rs'ro WHITMAN a Brianna, INC., en nnrnorr, rarcnrean, a cearcnarron or MICHIGAN I TOOL RETAINER Application filed July 12, 1929. Serial No. 377,691.

The present invention relates to improvements in retainers for tools, such as punches, dies and the like, and is particularly applicable to heavy duty tools adapted for use in metal forming operations.

riools of this character and the retaining means therefor in many instances are subjected to severe operating conditions. Thus, in punching metal of substantial thickness, heavy force is applied to the punch to shear the metal, and a. still greater'force is required te Withdraw the punch. The force required increases as the shearing clearance between the punch and the die is increased for greater thicknesses of metal, and is greater in hot shearing than in cold shearing.

rIhe tools must be removable from the retaining means so as to permit replacement because of Wear or changes in the character of the Work to be performed. To this end, the retaining means must be provided with a suitable lock for holding the tools in position during operation, and for Vreleasing the tools when desired. i

It will be evident that the retaining means, and particularly the lock should hold the tool firmly in place, Without lost motion, during the operation, and should be of sufficient strength to withstand the severe forces imposed thereon. Heretofore, serious difficulties have been met with in this regard.` In various prior retainers, the tools are not held securely in position, and the locks tend to crush or shear. Registration between the locks and the coacting parts on the tools is not accurate or positive, is dificult to effect when assembling the parts, and permits lateral play. In some instances, the locks also tend to injure the tools, and do not permit ease of replacement or substitution.

The primary objects of the present invention therefore reside in the provision kof a new and improved tool retainer in which the tool may be readily inserted and removed when desired, which serves to hold the tool securely in position, and which is capable of withstanding the forces imposed thereon.

A further object resides in the provision of a tool retainer which is simple, sturdy and relatively inexpensive in construction, which can be vmade with simple and easy machine operations, Which serves to effect an accurate peripheral registration, and which is effective to prevent substantial lost endvvise motion,

Further objects and advantages Will become apparent as .the description proceeds. .I-nthe accompanying draWing,;Fig. 1 is anV axial ,sectional view of a punch retainer Y embodying the features of my invention. f Figa 2- is a plan view of the retainer taken substantially along line 2-2 of Fig. 1.

Fig. 3 is a fragmentary sectional view taken along Iline 3.-3 ofFig. 1.

v Fig. L is aside View of the tool.

5 .isa perspective view of the latch member. l y 1 While the invention is susceptible of `various modifications and alternative constructions, I `have shown inthe drawing and Will herein describe in detail the preferred embede iment, but it is to be understood that I do not thereby intend to limit the invention to the specific formdisclosed, but intend to cover all modifications and alternative constructions falling Within the spirit and scope of the invention as expressed in the appended claims. Y 1

Referring. more particularly to the drawing, I have shown the inventionas embodied in a punch retainer, but it is to be understood that the invention is applicable to various types of tools.

The punch retainer constituting the eX- emplary embodiment of the invention comprises a retainer Which preferably iscylindrical in form and Which is formed With a central axial aperture 11, preferably a bore, extending therethrough. The `bore 11 is adapted toreceive the cylindrical shank 12 of tool, such as a punch 13, with a close .Sliding The retainer 10 is suitablyvmounted in a supporting member 14, and to this end the latter is formed With ajcylindrical bore 15 opening therethrough andiadapted to receive the retainer 10. Formed on the'upper end of the retainer 10 is a peripheral flange 16 seated against the bottom of a counter bore 17 formed in the upper end of the supporting member. A suitable backing plate 18Vals0V is disposed in the counter bore 17 against the upper end of the retainer 10, and lies substantially flush with the upper end of the supporting member 14. The latter with the retainer 10 and the plate 18 mounted therein, is removably secured, as by means of bolts 19 to a base 20, forming part of the operative element of the machine (not shown). It will be evident that when the supporting member 14 is removed from the base 20, the retainer 10 can be removed therefrom, and that when the supporting member is secured to the base, the parts are rigidly clamped in assembled relation.

Releasable means is provided for locking the shank 12 securely against the backing plate 18. To this end, the retainer 10 is 'formed in its upper end with a pocket or socket 21 of suitable form intersecting the upper end of the bore 11 and which opens to the upper end face of the retainer. In the present instance, the socket 21 is in the form Y of an inverted cone, the axis of which is inclined relative to the longitudinal axis of the shank 12. Preferably, the outer element of the socket is disposed vertically.

Formed in the upper end of the shank 12 is a suitable recess 22 which is adapted to be disposed in registration with the socket 21. Preferably the recess is in the form of a transverse angular notch comprising a flat lower surface 23 and a concave cylindrical upper surface 24. The inclination of the surface 24 is such that a normal thereto is inclined at a greater angle to the longitudinal axis of the shank 12 than the axis of the socket 21. lVhile the invention is not limited to speciiic angles or dimensions, in the present illustration the axis of the socket 21 is inclined approximately 17 3XL", and the normal to the surace- 24 is inclined at approximately 41"v to the longitudinal axis of the shank 12.

Pivotally mounted in 'the socket 21 for movement into and out of interlocking engagement with the recess 22 is a latch member 25. This member may be of any suitable shape, and in the present instance, is generally triangular in shape with the lower end loosely seated in the apex of the socket 21. 0f the latch member 25, the upper and lower ends are spherical in form, the radii being struck from a common center, and the radius of the free upper end is substantially equal to that of the cylindrical surface 24. The radius of the lower apex end of conical socket 21 and latch member 25 may be of any suitable size giving suificient spherical surface to carry the loads incident to the punch strip'- ping stresses. The sides of the latch memberlatory movement about the inner rounded end toward and from the shank 12.

Spring means is provided for urging the latch member 25 yieldingly into the shank recess 22. Preferably, this means comprises a bent compression spring 27 disposed between the latch member 25 and the vertical element of the socket 21, and secured at its vtree ends respectively to the free upper end of the latch member and the retainer 10. In the present instance, the retainer 10 is formed with a plurality of vertically spaced holes 28 opening to the socket 21 and adapted to selectively receive the outer cnd of the spring 27 so as to adjust the pressure thereof.

A suitable opening 29 is formed in the retainer 10 along the bore 11, and opens from the socket 21 to the lower i'ace of the retainer. This opening is adapted for the insertion of an instrument (not shown) whereby the latch member 25 may be moved against the force of the spring 27 out of the recess 22 to permit withdrawal of the punch 13.

It will be evident that l have provided a novel and advantageous tool retainer to hold the tool accurately, securely and releasably in position. Upon insertion of the tool, the

latch member 25 immediately snaps into the recess 22 to hold the tool against the backing plate 18. The member 25 also eli'ects and maintains accurate peripheral registration between the retainer 10 and the tool. The surface 24 and the spherical upper end of the latch member 25 meet in tangential relation. The latching angles are such that heavy pressure is applied to the member 25 only during the actual stripping operation, and is sub- Y stantially released at all other times. The construction is sturdy, compact and simple, and the punch is readily removable at all times even though a heavy pressure has ust been applied to the latch member.

I claim as my invention:

' 1., A tool retainer comprising, in combination, a base, a supporting member removably secured to said base, said member having an aperture opening therethrough and enlarged 75' at the inner end, a retainer mounted in said aperture and having an aperture opening therethrough, a peripheral flange on the inner end of said retainer seating in the enlargement o'l' said vfirst mentioned aperture, a backing plate in said enlargement between said base and said retainer, a conical recess formed in one side of said retainer and opening at its upper end to said last mentioned aperture, the axis of said recess being inclined to the longitudinal axis of said retainer, a tool having a sliding t in the retainer aperture and having a. lateral angular recess adapted to be in registration with said conical 1::

recess when said tool is in position against said backing plate, said angular recess delining a downwardly facing laterally con cave surface inclined at a greater angle to the axis of said retainer than said conical recess, a latch member having a rounded end pivotally seatedl in the apex of said conical recess, the free end of said latch member being rounded and movable into engagement with said surface to hold said tool against rotation and endwise movement, adjustable spring means engaging said latch member to urge the latter into said angular recess, and

an opening extending from said 'conical recess to the cuter face of said retainer.

2. A tool retainer comprising, in combination, a base, a retainer mounted cn said base and having an aperture opening therethrough, an inverted conical recess formed in one side of said retainer and opening at its upper end to said aperture, the axis of said recess being inclined to the longitudinal axis ot said retainer, a tool slidably engaging the retainer aperture and having a recess in one side adapted to be in registration with said conical recess when said tool is in position, said last mentioned recess defining a downwardly facing laterally concave'surface inclined at a greater angle to the axis of said retainer' than said conical recess, a latch member having a rounded end pivotally seated in the apex of said conical recess, the free end of said latch member being rounded and movable into latching engagement with said surface to hold said tool against rotation and withdrawal, and spring means engaging said latch member to urge the latter into said last mentioned recess.

3. A tool retainer comprising, in combination, a body having a tool receiving bore and provided at one side of the bore with a rec-ess, the axis of said recess being inclined to the longitudinal axis of the body, a backy ing plate carried by the body and closing the upper end of the tool receiving bore, a 'tool having a sliding fit in said bore and having a laterally opening recess adapted to be in registration with the recess in the body when said tool is in position against said backing plate, the recess in the tool defining a downwardly facing laterally concave surface inclined at a greater angle to the axis of said body than the recess in said body, means for holding the tool against the backing plate including a latch member having a rounded end pivotally seated in the lower end of the recess in said body and having its upper end free and movable into engagement with the concave surface aforesaid to hold said tool against rotation and endwise movement, and means urging the latch member into the bore for engagement with the tool including spring means adjustably connected to said body.

4. A tool retainer comprising, in combination, a body having a tool receiving bore and provided at one side of the bore with a recess, the axis of said recess being inclined to the longitudinal axis of the body, a backing plate carried by the body and closing the upper end of the tool receiving bore, a tool having a sliding it in said bore and having a laterally opening recess adapted to be in registration with the recess in the body when said tool is in position against said backing plate, the recess in the tool defining a downwardly facing laterally concave surface inclined at a A greater angle to the axis of said body than the recess in said body, means for holding the tool against the backing plate including a latch member having a rounded end pivotally seated in the lower end of the recess in said body and having its upper end free and movable into engagement with the concave surface aforesaid to hold said tool against rotation and endwise movement, and means urging the latch member into the bore for engagement with the tool including a substantially V-shaped spring having one end secured to a wall of the recess in the body and having its other end fixed to the latch member.

5. A tool retainer comprising, in combination, a retainer body having a tool receiving bore and provided at one side of the bore with an upwardly opening conical recess, thel axis of said recess being inclined to the longitudinal axis of the body, means for limiting the insertion of a tool in said bore, a tool having a sliding lit in the bore and having a lateral angular recess adapted to be in registration with said conical recess when said tool is in position against said limiting means, said angular recess defining a downwardly facing laterally concave surface inclined at a greater angle to the axis of said retainer than said conical recess, a latch member having a rounded end p ivotally seated in the apex of said conical recess, the free end of said latch member being rounded and movable into engagement with said surface to hold said tool against rotation and endwise movement, and means urging the latch member in engagement with the tool including spring means in the' conical recess and terminally connected to said body and latch member.

6. A tool retainer comprising, in combination, a retainer body having a tool receiving bore therein and provided at one side of the bore with a conical recess, the axisv of said recess being inclined to the longitudinal axis of the retainer body, means for limiting the insertion of a tool in said bore', a tool slidably engaging said bore and having a recess in one side adapted to be in registration with the conical recess when the tool .is in position, .said last mentioned recess defining a downwardly facing laterally concave surface inclined at a greater angle to the axis of said retainer than said conical recess, a latch member having a rounded end pivotallyseated in the apex of said conical recess, the free end of said latch member beingy rounded and lmovable into latching en#l gagement with said surface to hold said tool against rotation and withdrawal, and spring means engaging said latch member and body and urging the latch member int-o said last mentioned recess.

7. A tool retainer comprising, in combination, a retainer body having a tool receiving bore and provided at one side of the bore with an inverted conical recess, the axis of said recess being inclined to the longitudinal axis of the retainer, means for lmiting the insertion of a tool in said bore, a tool slidably engaging the bore and having a laterally opening recess adapted to be in registration with said conical recess when said tool is in engagement with said limiting means, a latch member having a. rounded end pivotally seated in the apex of the conical recess and having ts other end free and engageable with the recess in the tool, said free end being wider than the rounded end aforesaid and having a curved portion en# gageable with a wall of the recess in the tool, the construction of said rounded portion and tool recess beinO' such that the latch member is operable to hold the tool against rotation and withdrawal, and means maintaining latching engagement between the member and tool including a spring within the conical recess and terminally connected to the body and latch member.

8. In a tool holder, a body having a tool receiving more and provided at one side of said bore with an upwardly opening coni cal recess, means for limiting the insertion of a tool in said bore, means for holding said tool against said limiting means including a substantially triangular shaped member in the conical recess aforesaid and operable as a prop for a tool in the bore, the lower extremity of said member being rounded and slidably engaging the lower end of the recess, said lower extremity being free with respect to said body, the upper extremity of said member being free and engageable with a tool in the bore, and means within the body urging the free extremity of said member into the bore for propping engagement with a tool therein including yieldable means connected to the body and fixed to the member whereby the sliding engagement between the lower extremity of said member and the lower end of said recess will be maintained.

9. In a tool holder, a body having a tool receiving bore and provided at one side of the bore with a recess, means for limiting the insertion of a tool in said'bore, means for holding said tool against said limiting means including a latch member within the recess aforesaid and operable as a prop for a tool in the bore, the lower extremity of said member being rounded and slidably engaging the lower end of the recess, said lower extremity being free with respect to said body, the upper extremity of said member being free and enga-geable with a tool in the bore, and means within the body urging the free extremity of said member into the bore for propping engagement with a tool therein and maintaining the sliding vengagement between the rounded end of the member and the lower end of the recess, including yieldable means connected to the body and fixed to the member.

l0. In a tool holder, a body having a tool receiving bore and provided at one side of said bore with a recess, means for limiting the insertion of a tool in said bore, means for holding said tool against said limiting means including a latch-member in the recess and operable as a prop for a tool in the bore, the lower extremity of said member slidably engaging the lower end of the recess and being free with respect to said body, the upper extremity of said member being free and engagea'ble with a tool in the bore, and means within therecess urging the free extremity of said member into the borefor propping engagement with a tool therein and operable to maintain the sliding engagement aforesaid between the lower extremity of said member and the lower end ot the recess, including a substantially V-shaped spring terminally connected to said latch member and to a wall of said recess.

In testimony whereof, I have hereunto affixed my signature.

CARROLL R. ALDEN. 

